My router :Cisco 2821 (revision 53.51) with 239616K/22528K bytes of memory.System image file is "flash:c2800nm-advipservicesk9-mz.124-24.T8.bin"turn on the service policy, line protocol is disabledConfig:interface Tunnel10 description #To TEK-XXXXX-R...

While upgrading Unity Connection (publisher) from 2.1.2 to 2.1.5 we got a  message saying that the upgrade is not allowed. Is there any known  reason for that?A part of the output we got during the upgrade process is presented in the following :Statu...